Mobile paint making and spraying apparatus



Oct. 8, 1968 D. D. PIPKINS ET AL 3,404,839

MOBILE PAINT MAKING AND SPRAYING APPARATUS Filed Dec. 5, 1966 5 Sheets-Sheet 1 n N 3 3 Q0 71968 0.0. PIPKINS ET AL 3,404,839

MOBILE PAINT MAKING AND ISPRAYING APPARATUS Filed Dec. 5, 1966 s Sheets-Sheet} Oct. 1968 D. D. PIPKINS ET AL 3,404,839

MOBILE PAINT MAKING AND SPRAYING APPARATUS Filed Dec. 5, 1966 5 Sheets-Sheet 5 United States Patent 3,404,839 MOBILE PAINT MAKING AND SPRAYING APPARATUS David D. Pipkins, Gainesville, Fla., and Angelo F. Deposta, Chicago, Ill., assignors to The Yalspar Corporation, Rockford, 11]., a corporation of Delaware Filed Dec. 5, 1966, Ser. No. 599,258 Claims. (Cl. 239-113) This invention relates to a mobile paint making and spraying apparatus.

In the paint industry, the term latex has come to be accepted generically as a description of a water-thinned paint containing any of the emulsified polymers. Presently, latex paints have a vehicle of emulsified butadienestyrene, polyvinyl acetate, or acrylic, and modifications or blends thereof. These paints have water added during their manufacture in an amount of about 30% by weight. It can be seen that a large amount of the shipping weight of latex paints is merely water. Accordingly, it is a general object of the present invention to effectuate savings by alleviating the shipment of water.

It is an object of this invention to provide a mobile apparatus, movable from job site to job site, which can manufacture paint from raw materials at the job site.

Another object is to provide an apparatus in accordance with the foregoing and in which the newly manufactured paint can be pumped to a spray gun for application.

Still another object is to provide a mobile paint making and spraying apparatus which includes a new and useful drive system for driving the paint making impellers and for selectively adjusting the speed thereof.

These, and other objects and advantages of the present invention, will become apparent as the same becomes better understood from the following detailed description when taken in conjunction with the accompanying drawings, wherein:

FIGURE 1 is a top view, partly diagrammatic, of an embodiment of the present invention;

FIG. 2 is a view, partly diagrammatic and partly sectional, along line 22 of FIG. 1;

FIG. 3 is a diagrammatic view of the hydraulic system of the present invention;

FIG. 4 is a diagrammatic view of the pneumatic system of the present invention along with a showing of the water and material lines; and

FIG. 5 is a perspective view of a grinding impeller utilized in the present invention.

Reference is now made more particularly to the drawings which illustrate the best presently known mode of carrying out the invention and wherein similar reference characters indicate the same parts throughout the several views.

The apparatus of the present invention is advantageously movable from job site to job site. Accordingly, a truck, generally designated by the numeral 10, is provided with a rearwardly extending frame 11 adapted to support a bed 12. As is conventional, the truck is provided with wheels 13 and a cab 14. The truck conveniently has paneled walls 15-18 and a roof 19 to provide an enclosure along with the bed 12. Wall 16 is provided with a vent opening 16a for a purpose which will hereinafter become apparent, and walls 17 and 18 are provided with door openings 17a and 18a, respectively, to provide entrance into the enclosure. The parts thus far described are conventional, and further description is deemed unnecessary. It should be understood, however, that the present invention is not limited to a truck of this nature and that the apparatus hereafter described may be mounted on other movable vehicles such as a trailer.

As best shown in FIG. 1, an air storage tank 22 is supported on bed 12 and is connected to receive and contain air under pressure from an air compressor 23 conveniently mounted on air storage tank 22. The compressor is advantageously driven by a gas engine 24 as through a belt drive 25. Motor 24 is also conveniently mounted on air storage tank 22 and is provided 'with an exhaust pipe 24a which conveniently extends through vent 16a.

A pair of generally cylindrical grinding and mixing tanks 31 and 32 are conveniently mounted adjacent wall 17. Each tank is advantageously a fill-gallon size and arranged for grinding to suspend the pigments in water and for mixing the pigment-water mixture with a latex emulsion to form paint. Tank 31 is provided with a hinged cover 33 which may be opened for placing a quantity of materials in the tank. A valve drain line 34 communicates with the bottom of tank 31 and extends through bed 12 for draining the tank, as after cleaning. A hydraulic motor 35 is mounted on the top of the tank as by bracket 36, and is coupled to a shaft-37 which extends generally coaxially in the tank 31. A grinding impeller, generally designated 38, is rotatably mounted on shaft 37 and preferably adjacent the bottom of tank 31. Preferably, the grinding impeller has a diameter about one-third the diameter of the tank. The apparatus described in conjunction with tank 31 is duplicated for tank 32, and the above description applies thereto. Accordingly, similar parts are designated by the same number followed by the postscript prime and further description is deemed unnecessary.

' The grinding impeller, generally designated 38, is illustrated in detail in FIG. 5 and is of the type sold by The Cowles Dissolver Company, Inc. of Cayuga, New York under the trademark Hi-Shear. The impeller 38 includes a generally circular flat disk 38a conveniently mounted on shaft 37 by a fastener 37a extending therethrough. Washers 39, 39a may be provided, if desired. A plurality of saw-like vanes 38b is arranged around the periphery of the disk and generally perpendicular to the planeof the disk. Alternate vanes are disposed in opposite directions, as shown. The impeller illustrated is arranged for rotation in the direction of arrow 40 and the leading edges 380 of the vanes are generally perpendicular to the plane of the disk.

The grinding impeller 38 of the type described, having a diameter approximating one-third of the diameter of the tank and rotated at a peripheral speed of about 5,500 f.p.m., will adequately perform the grinding operation. At this speed, the impeller imparts high velocity to the material and creates a turbulent zone of intense energy dissipation. It has been found that the majority of the kinetic energy is used for hydraulic attrition in a distance of about two inches from the impeller vanes 38b. Rubbing of the particles of pigment and other solids on each other and against the liquid causes a shearing action which contributes to the rapid hydraulic attrition mentioned above. Also, the impeller imparts high velocity to the material at various directional differentials which results in particle collisions which further grind the pigments. Beyond the turbulent zone mentioned above, the movement becomes laminar and divides at the vessel Wall, assuring complete circulation of the entire batch. By use of the particular impeller described, the turbulence does not interrupt the fiow pattern.

A multiple storage tank, generally designated 42, is mounted on bed 12 conveniently adjacent wall 16. Multiple storage tank 42 is advantageously provided with a divider reservoir 44 and a lower water reservoir 45. Water reservoir 45 is provided with an air inlet 46 adjacent the top thereof, and this is connected to air storage tank 22 by means of line 47, diagrammatically illustrated in FIGS. 1 and 4. This serves to pressurize a supply of water in water reservoir 45. An outlet conduit or water line 48 communicates with the bottom of water reservoir 45 and leads to branch conduits 51 and 52 which empty into tanks 31 and 32, respectively. Valves 53 and 54 are interposed in conduits 51 and 52, respectively, to control the flow of water into their respective tanks 31 and 32. The quantity of water drawn into tank 31 or 32 may be measured in any convenient manner as by metering or by markings on the interior of the tank.

In manufacturing paint with the present apparatus, a preselected quantity of water is drawn into a tank, for example tank 31, and a preselected quantity of a pigment or pigments is placed into the tank through the access opening provided by lifting hinged cover 33. A wetting agent such as potassium tripolyphosphate is added and the mass ground at a high speed to suspend the pigments in the liquid. Naturally, the quantities of each ingredient will be based on a preselected paint formula. As previously described, grinding impeller 38 rotated at a peripheral speed of about 5,500 f.p.m. will perform this grinding operation. As explained above, hydraulic motors 35 and 35 are provided for rotating their respective grinding impeller. These motors are advantageously driven by a variable-delivery pump 55 driven by gas engine 24 through a shaft 56. The delivery of pump 55 may be varied by means of a control handle 57 conveniently mounted on the pump. Pump 55 is connected to hydraulic reservoir 44 by means of conduit 58 to draw a quantity of a suitable hydraulic fluid therefrom. An outlet conduit 59 leads to a 3-way valve 60 for selectively directing the fluid through conduit 62 to motor 35, or through conduit 63 to motor 35, or to both, if desired. Return conduits 64, 64' return the flow of hydraulic fluid from the motors to reservoir 44. A bypass conduit 65 is connected to conduit 59 and is provided with a bypass valve to control the flow of fluid therethrough back to reservoir 44. Hydraulic motors 35 and 35' are provided with vent lines 68, 68, respectively, to collect any hydraulic fluid which may pass the motor seals. Vent lines 68 and 68' lead back to reservoir 44, as best shown in FIG. 3. The hydraulic system is provided with a filter 69 and a pressure gauge 70 in the usual manner. Gas engine 24 must be of sufficient size to drive both compressor 23 and hydraulic pump 55 simultaneously, and the various components of the hydraulic system must be of sufficient size to rotate the grinding impeller 38 or 38 at the aforementioned peripheral speed. In this manner, the impeller can operate to grind the pigments and suspend them in the water, as described.

After grinding the pigments in one tank, an emulsion is prepared in the other tank. In the other tank, a preselected quantity of a latex emulsion is added to a preselected quantity of water along with a coalescing agent in accordance with the selected paint formula. A quantity of fungicide may be added along with a quantity of ethylene glycol to help prevent freezing. The second tank ingredients are mixed at a low rate of speed compared to that mentioned above, for example about 100 r.p.m.

The materials from the grinding operation are added to the materials in the second tank, or vice versa, and these combined materials are mixed to form the paint product. This final mixing is performed at a low rate of speed, comparable to that mentioned above. Since the same tank may be used for both grinding and mixing, it is important that the speed of the hydraulic motors be variable. In the present embodiment, such speed control is accomplished by varying the delivery of pump 55 as described above. It is contemplated that other speed controls could be utilized, for example individual controls for each pump. With such individual controls, the grinding 4 and emulsion preparation could be performed simultaneously, if desired.

The transfer of materials from one tank to the other is performed by means of a pneumatic pump 72 mounted on a panel 73 connected to tanks 31 and 32. An air line 74 leads from air storage tank 22 to an air metering valve 75 conveniently mounted on the top of pneumatic pump 72 and communicating therewith for controlling its speed. Material lines 76 and 77 communicate with the bottom of tanks 31 and 32 respectively and are joined by a T-connection to material line 78. Pneumatic pump 72 is interposed in material line 78 for pumping material therethrough. Material lines 76 and 77 have valves 76:: and 77a, respectively, which may be selectively opened or closed to select the tank from which the material is to be pumped. The pump outlet is connected by a T-connection to branch lines 81 and 82 in which are interposed two-way dump valves 83 and 84, respectively. The two-way dump valves 83 and 84 are operative to block flow, divert the flow through a dump line 81a or 82a back into tank 31 or 32, respectively, or to allow the flow to continue to a pair of flow control valves 86 and 88 (see FIG. 4). Flow control valve 86 controls the flow of material through a material line 90 to a spray gun 91 and is operative to eliminate flow fluctuations to the gun. An air line 92 is connected to the gun and to air storage tank 22. An air regulator 93 is interposed in line 92 for accurate regulation of atomizing air to spray gun 91. A second material line 94 may be connected to flow control valve and fluid pressure regulator 88 to supply material to a second spray gun 95, if desired. Under such condition, a second air line 96 may be connected to air regulator 93, as illustrated in FIG. 4, or may be connected to air storage tank 22 and be provided with its separate air regulator. Thus it can be seen that pneumatic pump 72 is operative to transfer materials from tank 31 to tank 32, or vice versa, and is also operative for pumping the manufactured paint to spray guns 91 and 95.

An apparatus is provided for drawing water from water reservoir 45 to clean the various tanks and material lines. For this purpose, a water line 101 is connected to water line 48 and to the base of material line 78. A valve 102 is arranged to control the water being fed into material line 78. In this manner, pump 72 can circulate the water through the various material lines 81, 82, 90 and 94 to clean the lines and also to clean spray guns 91 and 95. No water need be placed in tank 31 or 32 for such cleaning. This is advantageous if it should be desired to store paint in the tanks. If it is desired to clean the tanks, a hose 103 is connected to water line 48 and is provided with a spray nozzle 104 for washing the interior of tank 31 or 32 and the impellers and shafts therein. This wash water may be drained through drain 34 or 34' or pumped through the system by pump 72, if desired. By virtue of the pressurized water system it is possible to clean one of the tanks and drain it through its drain while pumping paint through the other tank to one or more spray guns.

As an example of how the present invention is utilized, it can manufacture paint based on the following latex formula for 50 gallons of paint:

Lbs. Water (3.7 gallons) 31 *Potassium tripolyphosphate 1 Tamol 731 1 Emulphor EL-719 1 /2 3% of 4,000 cps. Methocel 65 H6. grade 50 *Rutile titanium dioxide 162 /2 *Isco 1240 silica 59 *Calcium carbonate 49 *Celite 281 9 Polyglycol P-1200 1 Ethylene glycol 7%. Butyl Cellosolve acetate 4 Troysan PMA30 1 /2 Colloids 581B /2 These materials are placed in the grinding tank and dispersed or ground for approximately 20 minutes and then mixed with the materials in the other tank, as follows:

Lbs. Water 63 Polyco 804PL (PVA emulsion, 55% solids) 120 /2 These are adjusted for viscosity with 63 lbs. of water and for 3% 4,000 cps. Methocel (90 H.G.-D.G.S. grade). This yields about 50 gallons.

Since the manufacture of paint with the present apparatusis to take place at the job site, the various raw materials are prepackaged. They may, for example, be packaged in quantities for a ten gallon standard mix; however, this will vary as desired. In the above formula, the ingredients marked by an asterisk are solids and can be packaged together in an amount for the standard mix. The liquids to be added in the grinding operation may also be packaged together, except the mercury (Troysan PMA30) and the butyl Cellosolve acetate. Each of these latter two is packaged separately. Another package would contain the liquid latex emulsion to be placed in the second tank. Thus there would 'be five packages shipped to the consumer who would obtain the water from any convenient source.

The paint is manufactured in the manner previously described. In this example, there are 19 gallons of Water added to a 50-gallon batch, or 26% of the weight of the paint. This would be the savings in shipping costs in using this paint formula. Additionally, fresh paint is always assured, and it is ready to spray from the tank as soon as manufactured. It is deemed obvious that the manufacture can be accomplished in transit while going to the job site.

While a preferred embodiment of the invention has herein been illustrated and described, this has been done by way of illustration and not limitation, and the invention should not be limited except as required by the scope of the appended claims.

What is claimed is:

1. In a truck mounted paint making and spraying apparatus, the combination of: a generally cylindrical grinding tank on the truck and having an access opening for placing a quantity of pigment and wetting agent therein, means for supplying a quantity of water to the grinding tank, a shaft extending generally coaxially in the grinding tank, a grinding impeller mounted on the shaft, motor means for rotating the grinding impeller at a speed to suspend the pigment in the water, a second tank on the truck for receiving a latex emulsion, pump means for transferring thewater-pigment composition to the second tank, means for slowly mixing the composition and emulsion in the second tank to make a paint, conduit means communicating with the second tank for carrying the paint therefrom, said pump means operative to pump the paint through the conduit means, a spray gun at the end of the conduit means, and valve means for controlling the flow of paint through the conduit means.

2. The combination of claim 1 wherein the grinding impeller is generally circular and has a diameter approximately one-third the diameter of the grinding tank, and the grinding impeller is rotated at a peripheral speed in the range of about 5,500 f.p.m.

3. The combination of claim 1 wherein the means for mixing in the second tank includes an impeller in the second tank, and a hydraulic motor for driving the impeller; means for supplying a quantity of water to the second tank; and including a reservoir for holding a quantity of hydraulic fluid; a hydraulic pump; hydraulic conduit means connecting the hydralic motor, pump and reservoir; and means for controlling the speed of the hydraulic motor whereby the impeller may be operated at one speed for grinding and at a slower speed for mixing the waterpigment composition with the water and latex emulsion.

4. The combination of claim 1 wherein the motor means includes a first hydraulic motor, the second tank has a grinding impeller coaxially mounted therein and a hydraulic motor for rotating the grinding impeller at a speed sufficient to suspend pigment in water, and the pump means is operative for transferring material from either tank to the other, and including hydraulic conduit means leading to the hydraulic motors and hydraulic pump means for supplying hydraulic fluid therethrough to the hydraulic motors, and means for controlling the speeds of the hydraulic motors whereby the impellers may be operated at said speed to suspend the pigment in the water and at a slower speed to mix the emulsion and water-pigment composition, whereby the functions of the tanks are interchangeable.

5. The combination of claim 1 wherein the pump means comprises a pneumatic pump mounted outwardly of said tanks, and including a source of compressed air, a first air line connecting the pneumatic pump to the source, a second air line connecting the spray gun to the source, and an air regulator interposed in the second air line to regulate the flow of air therethrough.

6. The combination of claim 1 wherein the means for supplying a quantity of water includes an enclosed water reservoir on the support; the motor means for rotating the grinding impeller includes a hydraulic motor; and the pump means for pumping the paint includes a pneumatic pump; and including an internal combustion engine; a compressor driven by the engine; a compressed air storage tank for receiving air from the compressor; a first air line connecting the air storage tank and the pneumatic pump; a second air line connecting the spray gun and the air storage tank; a third air line connecting the air storage tank with the top of the enclosed water reservoir to pressurize the supply of water; a hydraulic fluid reservoir; a hydraulic pump driven by the engine; and hydraulic conduit means connecting the hydraulic motor, reservoir, and pump.

7. In a truck-mounted paint making and spraying apparatus including a spray gun and paint conduit means for carrying paint thereto, the combination of: first and second tanks on the trucks, each tank having an impeller mounted therein, first and second hydraulic motors for driving the respective impeller at one speed sufficient to grind pigment and suspend it in water, hydraulic conduit means connected to the hydraulic motors, a hydraulic pump connected to the hydraulic conduit means to supply fluid under pressure thereto, means for driving the hydraulic pump, means for regulating the speed of one hydraulic motor to regulate the speed of its impeller at least between a speed approximating said one speed and a slower speed for mixing the pigment-water composition with a latex emulsion, means connecting the paint conduit means to each tank, and pump means disposed outwardly of the tanks and associated with the paint conduit means for pumping paint to the spray gun and for pumping materials from one tank to the other.

8. The combination of claim 7 wherein the first and second tanks are in juxtaposition, the paint conduit means includes a single conduit located intermediate said tanks and first and second branches leading therefrom, each branch communicating with the bottom of a respective tank and having a valve interposed therein to selectively block flow therethrough, and the pump means is mounted intermediate said tanks and connected to the single conduit, whereby the pump means is selectively operable to pump from either tank.

9. The combination of claim 8 wherein the conduit means includes a discharge conduit leading from the pumping means and having first and second branches, each branch leading to a respective tank and having a valve interposed therein for selectively controlling flow to the respective tank.

10. The combination of claim 8 including storage means on the truck for holding a quantity of water, and means operatively connecting the storage tank to said pump for supplying water thereto, whereby Water can be pumped to the spray gun for cleaning the same.

References Cited UNITED STATES PATENTS Goetz 2391l3 Sanders 239142 X Gleason 239172 X Vork 239-142 X 3,023,968 3/1962 Mitchell 239-142 X 3,135,499 6/1964 Brown 259-135 3,326,815 6/1967 Werner et al. 259-8 X OTHER REFERENCES Geisler, Dr. H. and Strobe], L.: German Auslegeschrift No. 1,164,947. Published Mar. 12, 1964.

M. HENSON WOOD, ]R., Primary Examiner.

VAN C. WILKS, Assistant Examiner. 

1. IN A TRUCK MOUNTED PAINT MAKING AND SPRAYING APPARATUS, THE COMBINATION OF: A GENERALLY CYLINDRICAL GRINDING TANK ON THE TRUCK AND HAVING AN ACCESS OPENING FOR PLACING A QUANTITY OF PIGMENT AND WETTING AGENT THEREIN, MEANS FOR SUPPLYING A QUANTITY OF WATER TO THE GRINDING TANK, A SHAFT EXTENDING GENERALLY COAXIALLY IN THE GRINDING TANK, A GRINDING IMPELLER MOUNTED ON THE SHAFT, MOTOR MEANS FOR ROTATING THE GRINDING IMPELLER AT A SPEED TO SUSPEND THE PIGMENT IN THE WATER, A SECOND TANK ON THE TRUCK FOR RECEIVING A LATEX EMULSION, PUMP MEANS FOR TRANSFERRING THE WATER-PIGMENT COMPOSITION TO THE SECOND TANK, MEANS FOR SLOWLY MIXING THE CMPOSITION AND EMULSION IN THE SECOND TANK TO MAKE A PAINT, CONDUIT MEANS COMMUNICATING WITH THE SECOND TANK FOR CARRYING THE PAINT THEREFROM, SAID PUMP MEANS OPERATIVE TO PUMP THE PAINT THROUGH THE CONDUIT MEANS, A SPRAY GUN AT THE END OF THE CONDUIT MEANS, AND VALVE MEANS FOR CONTROLLING THE FLOW OF PAINT THROUGH THE CONDUIT MEANS. 